Testing Ignition Coils and Fuel Injectors (Intentional Shutdown)

2014 Jeep Patriot 2.4 P0302 Cylinder 2 Misfire. Testing for Spark, fuel injection pulse and compression (cranking sound test). Even if you do not have a lab scope, you will still benefit from watching this process of determining the cause of the misfiring cylinder.
ScannerDanner Tools:
www.scannerdanner.com/tools.html
www.amazon.com/shop/scannerda...
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium www.scannerdanner.com/join-sc... There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

[@stationaryenginesworldwide]

great video guys! these systems you are working on change from year to year it seems. You guys are the best on the tube ....so glad to be a premium channel subscriber too

[@ScannerDanner]

They do but the fundamentals are the same, don't you agree? Thanks so much for your support! For others reading this, you can join ScannerDanner Premium here www.scannerdanner.com/join-scannerdanner-premium.html Hope to see you there!

[@hav2win]

I love how you're always trying to figure out different ways to educate us and challenge us to think on our own. Great video. Thanks Paul.

[@ScannerDanner]

Thank you!

[@gregorymorris8343]

Family is everything, your family is wonderful. Love seeing you guys working together

[@ScannerDanner]

thank you!

[@JamesBacarisas]

Mr. Danner, thank you for sharing with us your knowledge about testing and troubleshooting. Sharing is Caring.

[@MiniH0p]

I recently been watching a lot of your vids and iv discovered the power of a scaope. i got a used modis ultra, been playing with it all week. iv been impressing my teachers at school with my understanding of the the tool and wavefroms and its all thanks to you!

[@ScannerDanner]

Awesome! Thanks so much and welcome to my channel

[@asewamu]

I’m a simple man, I see a new SD video I watch it 🙌🏻 keep up the good work! Love watching your workflow without the need for diagrams on basic circuit testing. Really has helped me with efficient electrical testing over the years!!

[@sidalisayad8837]

every time i see one of your videos i learn a heck of things , even not to be a part changer but also to be i nice social engineer to the people to express the very issue of the car ,thank you very much sir

[@utubepremium4739]

Just want to say thanks for sharing your experience and knowledge .God Bless you and your family. Keep up the awesome work you do

[@douglash3129]

Hi again Paul and Caleb and everyone else there, every time I watch your channel I learn something, I like it!!!

[@theadmiral5425]

Another classroom moment...waveform before swapping the coils and the PCM shutting it off( 13:07 ) and waveform after swapping the coils ( 19:45 ). You can see the internally shorted coil in the waveform. 💡💡💡.....this is why I love SD, you cant beat visuals for learning.

[@ScannerDanner]

Thank you!

[@nicholassosa272]

i love this channel. I'm an entry level tech getting into the field and currently in school. Scanner Danner is doing way more than my school that cost almost $10K, Actually going thru the diag with real world examples and going thru the proper steps. I want to get real good at doing diags and electrical work given where the industry is heading. Thanks man ! I can't wait to save up money for the Book !

[@mule761]

Thank you for your videos they kick butt I'm always preaching ground ground ground no ground no current when will they ever listen thanks again

[@hondanation9375]

Great video Paul I appreciated all you can show

[@johnlenoir1023]

I love it please continue to do things the same way and I couldn't find a better person to learn from

[@CycloneCyd]

Brilliant video. Nice to see you getting 'old skool' with that spark gap tester. Here in the UK most mechanics seem to believe you cannot test coils which is why I did a video using the same tool, but it's also great to see a scope being used to back it up. As for the software shutting the coil down - that's probably an error in the software code. I'll bet Chrysler don't even know it as it's not a error that causes a problem in of itself. Probably poor communication between the Chrysler Engineer who wrote the ECU functionality spec and the software supplier.

[@ThunderbirdRocket]

The best camera shots , detailed coaching and diagnostic process rationale ! Thanks !!

[@ScannerDanner]

Thanks so much Thomas!

[@donniejohnson7499]

Another awesome video!!!!!! Paul Danner. From your friend . Don r Johnson. Proud I got to watch this video.

[@douglash3129]

Hi Paul and excellent camera man Caleb, you get these jobs because this is your thing and you are great at this you are a TEACHER!!!!!! and your Bro knows you love it.

[@kasundoph.788]

Very nice content boss danner.. i experienced like that mazda cx9...i scanned it P0202 it says there that cylinder number 2 misfire .. so we decided to exchange ignition coil number 1 and 2 and scanned again the dtc P0202 it means that nothing wrong with the ignition coil so we decided to check the injector number 2 and finally we found it..the injector number 2 was defective..after replacing the new one the vehicle was ok.. thanks boss danner for sharing your briliant idea..God bless to all of you and your family.. Philippines..

[@kalindambozi2356]

Thank for the video. Always learning new stuff

[@sohailrabani]

Great teacher you are Mr.Paul..cheers

[@dtandfam8100]

Appreciate the video Danner's! Never knew both inj. & coil. Would be shut down on a misfire. Cool find. Love the scope captures on this one too! Thanks for sharing!

[@LynxStarAuto]

Euro cars do this a lot.

[@menombakglobalis]

toyota was done like this on 2005 at toyota fortuner gasoline engine...

[@ThunderbirdRocket]

Really enjoyed the training !

[@dalebabbitt6185]

Awesome video, so much good information, thank you!!!!!

[@polnashautosgarage0001]

Hey Namesake,Keep up the good highly informative job

[@LorenKadison]

I like the nova in the back and love your videos thanx Danner 😊 🙏

[@nelsonnarciso1791]

Well done brother. Never seen this happen also very interesting

[@Huck_5]

You, good sir, are a dang genius.

[@thebaldmechanichardatheari1124]

My dad purchased a new 1967 Meteor Rideau 500 when I was a child. Remember driving it when I was older and the steering was very easy to turn. There wasn't much road feel when driving. Person had to be alert when driving. Lol Good Stuff

[@troysmith9453]

Question about that o2 is why wasn't it more clean is that normal?

[@stevehei8035]

Great find!

[@Pablo_Automotive]

Thanks a lot for another gran explanation.

[@whitetiger8652]

Thanks for the video.

[@cullenmiller8170]

Nice video and thanks for letting us tag along. That coil shutdown could turn into quite the rabbit hole if you didn't watch it on the scope. I used a former girl friend as a 9v battery tester and lets just say she was not very impressed with me. I wish I could have captured her face. 🤣🤣

[@DANNYN224]

Great video I was diagnosing aswell I would of swap the coils to see if the misfire is changed and clear the codes and rerun the engine to see if it has changed and looked at graphing on a scanner aswell

[@wilamyoukhana1109]

Your the best teacher Paul

[@robbycumby8019]

Awesome video Sir.

[@vinces8974]

That was an interesting case study to say the the least!

[@AKChryslertech]

I love your brothers sense of humor on that one! Hey brother it has a misfire...

[@ScannerDanner]

Love working with my brother

[@dazeboy79]

Thank you very much for the information! Very informative and great explanation of everything going on! I'm subscribing and watching more videos!👍👏

[@ScannerDanner]

I'm glad you're here. Welcome!

[@jeremyah78]

Looked like you were having a lot of fun on this one Paul!😅 It was a lot of fun to watch too! I wonder if they’re shutting the coil down to cool it before bringing it and the injector back on line in an effort to get it to fire some again? Sometimes cooling the windings will restore some continuity. I’m purely speculating… but maybe some engineer thought that might be a good ‘limp home’ strategy. We’ll likely never know😂

[@TheWaelabo02]

Thank you so much , no matter how old any system but always we learn. Thank you again, I have my owen Chanel and work in trucks ,heavy equipment, hybrid and electric cars but still learning from you .

[@michaelgalvin1024]

What's your channel?

[@TheWaelabo02]

@@michaelgalvin1024 Wael Ahmed Sorry most material with arbic lunguch.

[@ScannerDanner]

Post the channel link my friend

[@TheWaelabo02]

@@ScannerDanner kzbin.info

[@michaelgalvin1024]

Great editing, I don't miss the waffling🙏🙏🙏🙏😀

[@ScannerDanner]

Caleb makes me look better than I am lol

[@isalmankhan1]

Love it Perfecto👌 Thanks for sharing SD😍 Special Thanks to James & Caleb Danner👍 Love you Guy's, Stay Blessed❤

[@jackiemay9471]

hi paul in the uk i have worked on a few where no 1 cylinder is closest to flywheel i learned the hard way now if i am not 100% on where no 1 is i force a fault and use same scanner to tell which cylinder is where thanks for the video

[@robertmobileman8304]

great video and explantion.. good job guys..get yourself some 9v direct usb lithium rechargeable batteries for your amps clamp, i did the same thing always leave the switch turned on, saves buying lots of 9v batteries

[@ScannerDanner]

My new pico 4425A self powers my amp clamps (of course the amp clamp has been redesigned too but that definitely solves this problem right? Thanks!

[@AutomotiveServiceExcellence]

Great case study first time i see that computer shutdown both Thanks!

[@troysmith9453]

I'm at work right now but will be off at 2pm so I'll be back gotta see this on my 65 inch flat screen 😉

[@Nocturnal2010]

I thought I was the only one that deliberately smells the exhaust for hints on performance, or lack there of 🤣🤣🤣👍🏾👍🏾👍🏾 I love it 🤣

[@marknahts6948]

And the reason it does that, to protect the cat due to excess unburned fuel. It’ll destroy that cat for sure. Love your simple approach, I had no 02 codes to make sense of this condition. I have the exact engine with the turbo, and the O2 sensor was the last thing I swapped. Problem solved. Great diagnosis! I’m subscribed!

[@TheMotorm182]

Why wouldn’t the engineers include that in the error codes? If the ecm knows it’s shutting them down, it should report it as an error and would save a lot of confusion. Maybe Chrysler specific diagnostic software does? Your my favorite teacher Paul!

[@ETAI106]

Great video again.. 👊🏻😎👊🏻 At a scenario like that, should I examine the Spark Plugs as well?..

[@ScannerDanner]

Yes, they should just be changed on principle, using only the factory plug

[@miketeeveedub5779]

I wish every technician had your level of critical thinking and diagnostics skill, along with ethical and moral values. This could've been a parts cannon special (PCM, injectors, plugs, coils, and oxygen sensor ), but ended up being a simple coil replacement. Thanks for the showing us the ins-and-outs of such a common but potential misunderstood malady. Cheers!

[@LynxStarAuto]

Ahh a fellow VW tech? The ironic part is the cannon techs would have figured it out early in the cycle because coils are the first part they swap.

[@brianewer3905]

parts canon don't even test shit. they would have figured it out first try. they would buy a plug and coil first.

[@yanierolivera4678]

Would have been interesting to unplug an injector in a good firing cylinder to intentionally create a misfire and see if the computer would have shut down that coil. We still don’t know if the coil was turned off because it was faulty or because there was a misfire in that particular cylinder. Takes more KVs to fire a lean mixture. If shutting down an injector due to a misfire and to protect the cat, why not shut down the coil and protect it too from having to fire into a lean mixture…??

[@luisnavarro6511]

Hey Paul, any way you can make a video on testing direct Injector being stuck open or stuck closed ? Or is there one already ?

[@Tomcat8911]

Good video..dont assume but verifiable test.Saves time and money.thanks...basics again...lol

[@Santiago_Ordonez_]

Perfect... 👌

[@geoc7086]

Great video!! I am a subscriber for scanner danner premium!! Enjoy the content. I am also learning diagnostic methods in school. Would you recommend to get the snap on edge to use as a scope? Or get a pico scope ?

[@ScannerDanner]

It really depends my friend. You will need a scan tool too if you go with a Pico. I think for the cost comparison I'd get a pico and an Autel or Topdon scan tool combo and you'd still be less than you'd spend on a Verus Edge.

[@Victor664.1]

Saludos SD

[@gogoskull6289]

Hi I have a question if there are a different between the car’s inbound from USA and Europe and Asia in diagrams or the different is in the wires colors

[@emceecoldharted2419]

Intesting that they would do that, I wonder if they periodically reactivate the coil to check if it’s working

[@aamechanic8154]

You'd think by now manufacturer's would switch to a 3 wire coil and protect the ECM from over current faults...I think even new models from Ford and Chrysler still have 2 wire coils on certain applications

[@Discretesignals]

Chrysler likes to look at burn time from their coils, so the PCM needs direct access to the primary circuit. The ignition coil driver is protected in 2 wire coils from over current and uses a zener to clamp the kickback. They are fairly reliable. The three wire coils and circuitry is more expensive to manufacture, so bean counters can save money by using a more simple system.

[@Ranalla651]

Chrysler pperates different and worked for many years. New chryslers I believe are still 2 wire. Simple diag.

[@LynxStarAuto]

@@Discretesignals This is also a waste spark system. Which I always thought was dumb. Just working the coils needlessly for no benefit.

[@bornfacecheelo3395]

What is that tool called , the one used to check spark?

[@guillermoriverosbaez]

Great case study as always To see secondary ignition waveform on COP coils I use the Hantek HT308 extension cable, it is a good addition to look for. Also check the new Micsig Sato 1104 oscilloscope, it is a neat tool for the price and has automotive presets and also come with serial decoding for many buses

[@midnight-xpress1136]

It makes sense to shut the injector down, so as to not send raw fuel out the exhaust. Granted you don't smell the raw fuel out the tail pipe, but wouldn't that help the cat also. Unlike my 78 ford, granted not fuel injected, but I lose a spark on a cylinder and I'm killing swaths of mosquitoes and others following behind me. I know this for a fact seeing I lost spark on no.7 and was gassing a group of friends following me. Edit: You pretty much covered that at 32:20.

[@lilMookieDaDon]

My gm 3800 keeps doing it on x1 coil for number 2&5cyl ..it sparks but after it's warm it's intentionally cutting off .can u help please. I don't have a scanner like u

[@mikeydejon2148]

Like your vids your old one on k1500 with fuel pressure was my issue !! Where ya at in pa ? Wouldn’t mind bringing my stuff to you if not too far !

[@ScannerDanner]

My brothers shop is in Bethel Park Pa

[@codo7]

I imagine the coil is shut down to prevent a short within the primary from eating the driver. Pardon me, I mean that a short in the secondary winding could transfer to the primary thus. So they try to limit that event, I think.

[@jonathanlow5260]

Cool

[@antoniobarber8650]

I’m a diy’er and want to but a basic lab scope. I like the one from aes wave the uscope that you’ve used in your videos but came across a otc 2 channel one but haven’t seen much videos about it. OTC 3840F. What would you recommend for a first scope to own? Also I plan on buying your book

[@ScannerDanner]

I'm not familiar with that scope Antonio, I'm sorry. Thanks!

[@franksaccente]

What videos go over the basic understandings of DC Voltage, do you have videos of basic understanding on your premium? Please answer thank you

[@ScannerDanner]

Yes, many! www.scannerdanner.com/scannerdanner-premium-chapters/basic-electrical-concepts.html

[@Portuguese-linguica]

Danner was a part changer ?

[@howlinhog]

Oooooh that was an annoying reminder. I have that same Snapon amp clamp. The switch can be accidentally turned on wayyyyy too easily. My fluke clamp, same thing. I'm a mobile tech and working out of a bag can be a real hassle in that way.

[@wilamyoukhana1109]

Not too damage the cat it’s good design I like it I hope they make all cars like that

[@BigDogDiagnostics]

I’ve seen those Chrysler coils go bad and short the ECM driver several times.

[@chucklemberg4968]

Just started watching videos on your channel because you appeared on videos on the ETCG and ETCG1 channels. Two things I really liked about this video: 1. How logical and systematical the actual diagnosis is and how you are able to present it in that manner and 2. How you were able to work through something that you had never experienced before. I was hoping you (or someone on your channel) can clear up some questions I have about scan tools. It is my understanding that the data that can be scanned is dependent on the year, make, and model of the vehicle being scanned - i.e., my 1996 Dodge Intrepid 3.5L is limited in the number of sensors it uses and, therefore, limited in the number of PID's a scan tool can monitor. On the other hand, a scope can provide additional information due to the fact that it can be directly connected into the wiring. My question is this, how can I tell exactly which PID's a scan tool will monitor on my vehicle?

[@ScannerDanner]

It's exactly as you said. All of it. The modules and data PIDs and even bi-directional controls, will be a factor of the car itself AND the scan tool being used.

[@chucklemberg4968]

@@ScannerDanner Appreciate your reply. So, in my case, I know that the scan tool that I use can access more PID's than my car provides info for. But, is there any way to determine exactly which PID's my car can report? Specifically, the shop manual for my vehicle lists multiple transmission codes for my vehicle, but I have never been able to find a way to access them.

[@ScannerDanner]

@@chucklemberg4968 no there really isn't however if your 96 has a separate transmission control module and you can't access it, then it sounds like you're scan tool is just an obd2 global scan tool (minimum function).

[@chucklemberg4968]

@@ScannerDanner Thanks. I really appreciate your taking the time to reply. I will definitely keep watching your videos.

[@RotoRCol]

just want know if the arrow of the amp meter goes in the direction of current flow, it means from negative to positive or viceversa? I ask this because in real world the current flow from the negative to the positive

[@ScannerDanner]

Conventional theory current flow (direction of arrow)

[@andrewdouglas2609]

Hey Danner i am a big fan of your channel i watch your videos all the time to help solve problems i am having with my car most times i get right to the problem after watching but this one have me pulling my hair out so to speak, i have an 05 dodge magnum rt with U codes up the wazoo, lost communication with alot of my modules. U0019, B223B, U0141, U0020 etc. what direction should take ?

[@ScannerDanner]

Start by finding out what's NOT talking. The u codes in the modules that are talking will be your guide

[@nickayivor8432]

📷 man Caleb thank you 🎥 footage great loved it Take care PROFICIENT Sir ScannerDanner My teacher Start to finish loved it tutorial thank you very much . Bottle of water 💧 very good for your body 💧 Take care and have a great Weekend with all your family around you PROFICIENT Sir ScannerDanner From Nick Ayivor from London England UK 🇬🇧

[@mrgalea100]

Why is it that an open circuit reads as “current too high”? Is this related to bis voltage and do you have a video on that

[@ScannerDanner]

What time frame my friend?

[@andyglenndaniel6945]

Pf, but it was a good morning my friend was there and it it a great time for me

[@aidensketches2144]

My Jeep does this same thing but only for cylinder 2 . I put new spark and swapped all coils but still only cylinder 2

[@ScannerDanner]

Is the spark on that coil?

[@Benny-dv7xm]

Subject Vehicle: 2004 Subaru Forester X EJ25 AWD QUESTION: Will this manufacturer shut down the injectors and the shared coil pack? The motor compartment harness does not match the ecu side indicating a change in harness. Somehow someone linked the injector power leads and egr power leads from 6 seperate pins to one single stretch of the same diameter wire and then as if they realized they screwed up they reconnected (6) lengths of the original diameter wire off that short singular piece of wire to go to (4) injectors and (2) to the egr. Initially when I got the car it only displayed evap leak code, arf heater circuit code, cat icon, and egr code. The egr heats up bad but eliminates the code with it connected but to keep it from burning out I disconnected those two wires. The testing of the egr resistence was in range but I didn't find a correct electronic wire diagram and schematic to guarantee that the pinouts were correct for those other (4) leads (1) on each motor winding potentially being for a position sensor. If I recall correctly voltages were correct koeo and koer. The physical condition of the valve mechanism was relatively clean and east to move and the feed tube and housing were free flowing gasses through the tube and valve body and intake. QUESTION: Will voltage or amperage vary enough through the (6) power leads going to one length of wire for a foot and then reconnecting four lengths of seperate injector leads and two egr leads enough to interfere with the pulsing flow of the injectors and cause the car to constantly run rich. I did cleaning of injectors through through a whole quart of fuel addative after which is when I started noticing intermittent fuel smell from the air intake housing suggesting for possible leakage. Removing them and manually cleaning the injectors yielded no visible restrictions and they sound and feel like they are operating when installed but with varing intensity one from the other and seemly intermittent feeling of strength within each injector unit. With the exhaust dropped 1&3 had no flame where 2 & 4 had a pretty blue flame where #4 was steady burning and 2 was intermittent burning to me seeming to indicate excessive rich. NOTE: that now I SEEM to have a parasitic loss of which is potentially through the alternator because even with an isolator switch on the negative side in the circuit after a big 3 upgrade seemed to cause the battery to drain quicker and as if I am not getting the same charge out of the alternator the battery never seems to get up to full charge even with lengthy idle times. So end of August after doing more research I bought a high amperage alternator kit to make certain I would have enough amperage and voltage to meet this system requirements which the car is amperage wise under supplied from the subaru design and symptomatic with the install of the big 3 as if the alternator has a parasitic draw which reduces or stops by disconnecting the big negative kable and now with the battery isolator switch. I had bought an alleged high amp alternator with the kables and battery kable terminals although the alternator from dc Power Engineering and through their associates out of Nations starter and Alternator were advertised and stated to fit this car as a direct fit it doesn't fit, it will take modifications to get it to just loosely drop into position in the alternator bracket and then it still doesn't look like the front housing pivot side face will clear the ac belt nor will it necessarily clear the intake on the back so even if it made through shipping I can't fit the unit without making front cover modifications and still potentially need to make bracket and belt modifications to clear the oil sending unit. I requested a return authorization because for what was supposed to be direct fit for $919 total sale the only thing useable is the big 3 kables but not certain if they are constructed correctly because they lied about these alternators being direct fit it is clear they never fitted these units into a subaru if they had they would have had to redesign the front cover and or design a bracket alteration. They refused to send me a legal warranty update to make the modifications and guarantee me that if I make those modifications and it doesn't work from shipping or assembly errors they would take their unit back. In between fighting to get my money back I was checking today to get from a local partshouse a tribecca alternator to see if I can both give a limited upgrade to amperage and to eliminate potential parasitic questions. Rebuild kits unfortunately are not available locally or I would have gotten one. So now I amp trying to address the power supply issues but before I don't believe they existed so I still need to answer the previous questions that existed before the current alternator question and you seem like you would recognize these situations problems quickly given weak supplies of proper technical and troubleshooting information for free on the internet. I have to live from this and I am dirt poor while learning to retrain myself through this vehicle and hoping to get up to a level to get my health back and get a great paying job. I need the help feedback please!! Thanks and Good Day😁

[@ScannerDanner]

I've never seen that on a Subaru. I've never seen this ever, until now, but to be fair, I'm no longer on the front lines.

[@Huck_5]

How would I test for spark without the gadget/tool? Just pull the plug out and visually check? Would I have to ground the plug, or no?

[@ScannerDanner]

Incandescent test light is what I use all the time. Check out my chapter 22 playlist (right here in YT) for more

[@tedhartman3277]

What is a Power Ground? is that the same as a switched power ground? IE and transistor controlled ground?

[@ScannerDanner]

A power ground is usually a main ground for some type of module or computer system

[@dalenassar9152]

I cant find the answer to this question ANYWHERE.... How much current does the secondary output of a typical ign. coil flow during the spark...just looking for a ballpark answer. THANKS FOR ALL OF YOUR GREAT VIDEOS!!!!!!!!

[@ScannerDanner]

That's because you can't really measure it. It is very high voltage but very low amperage is the best answer I got for you. There is never a time where there would be a diagnostic advantage to measuring secondary current. We only care about how far the spark can jump and the voltage the coil can produce.

[@dalenassar9152]

@@ScannerDanner Thanks for the quick reply. The reason I needed the secondary current value, is because I am designing a circuit in which the coil acts much as it would in a car. For part of this circuit, I need to block (and pass...I won't get into detail here) the high voltage with reverse diodes. I have no problem with the voltage (I'm using 2 or 3 microwave oven diodes in series). Most are rated at a forward current of 250mA...some are 450mA. Perhaps you will know if this is (=MUCH= more than) significant for the intervals when the HV secondary current must flow in the forward direction, since I can't find ANY CLUE of the sec. current range. AGAIN, GREAT VIDEOS EVERY TIME!!!

[@mrv4757]

Well, you said in the beginning that coils 1, 3 and 2, 4 are paired. If engine computer shuts 1st coil down the 3rd would go off at the same time?

[@ScannerDanner]

No, just the power supply is what I was talking about

[@menombakglobalis]

just power supply, ground, & IGF pararel on all coil... The IGT have independent driver/control from ecm to every coil... The IGF have 5v stanby,, The IGT have signaling 5v

[@spelunkerd]

I don't understand why the PCM can't have data-pids to highlight the use of substituted values, or to help quickly identify a computer decision to disable injectors, etc .

[@ScannerDanner]

We did kind of see that in the p.w. command to the injector right?

[@Discretesignals]

Manufacture could be shutting the coil off to protect the coil from having to operate in a lean cylinder. Much harder for a coil to push a spark out (higher KV) with out fuel as a conductor. Some reasons for a failed secondary or spark burning out the side of the boot is vacuum leaks, worn out plugs, or injector flow/pattern issues.

[@ScannerDanner]

I like that thought. A lean misfire is definitely stress on the coil

[@5Dale65]

First I thought it was just for lowering the energy consumption and alternator load, for the car is already weaker with that one cylinder out

[@ScannerDanner]

@@5Dale65 honestly that's probably part of it too

[@tigerksewsankar7667]

Sd is the men thank you and your son.

[@12mak]

I was looking for that intentional shutdown lecture video in the description lol Thanks for the videosp

[@ScannerDanner]

kzbin.info/www/bejne/rGrGpKNpYpmJidU I think maybe I was referring to this one?

[@12mak]

@@ScannerDanner Thanks

[@GarnConstructionInc]

Great video on computer behavior. It seams that a lot of mechanics always change the plug when a coil goes bad. My question is could a fouling plug cause enough over current to burn the coil winding open or shorted? Our corolla had a bad coil after 100k so I ordered two and changed all the plugs. Before the parts arrived it lost another coil. After the new plugs the remaining 2 coils have been fine.

[@johnhubert7438]

Worn plugs cause the coils to work more to jump the worn plug gap

[@ScannerDanner]

Fouling, no, because that is an easier path, so the coil would be stressed less, not more. An open is a different story. Sounds like just bad new parts. What's Eric O say? New = Never Ever Worked

[@GarnConstructionInc]

@@ScannerDanner You caught it! I should have said high mileage or worn, my bad. Then the larger gap requires a larger voltage inducing a larger current, and heat, in the coil. So if the plugs are left in beyond the service interval you might be stressing a "possibly lower tolerance to failure Or just poorly mfg" coil over plug system. I don't recall ever replacing a coil in decades of a distributed system so curious about what caused the factory coils over plug to fail at roughly the same time.

[@CycloneCyd]

@@GarnConstructionInc knowing the auto industry as I do, I would say that will be down to manufacturing consistency.. The chances are that the original factory fitted coils on any individual engine came off the coil production line one after the other and are probably close to being identical. At least for companies like Toyota where Engineers rule the roost. Toyota probably have their coils nicely packed in liners. Companies like Ford or GM probably pack coils loose in boxes to save the cost of packaging because the bean counters rule, which leads to a more random distribution of parts (but also an increased chance of early life failure due to rough handling during transport. My tuppence hapenny worth anyway, in truth we'll never know.

[@GarnConstructionInc]

@@CycloneCyd #1 started misfiring first then was good for a month after a good cleaning. That was the warning sign to change the plugs I ignored. I forget the second but it may be as simple as location to the oil fill cap!

[@lakesautomotivediagnostics6509]

Excellent video, what’s the year make and model

[@ScannerDanner]

It's in the description of the video. 2014 Jeep Patriot 2.4 Thank you!

[@lakesautomotivediagnostics6509]

@@ScannerDanner my bad, I rarely look at the description of videos, I’m sure I will remember that now lol

[@ScannerDanner]

@@lakesautomotivediagnostics6509 I always try to add helpful info in the first few sentences of my descriptions. Thanks!

[@blow0me]

you would think the ecu/diagnostic tool should highlight that it is a deliberate shutdown to alert a technician. It knows it has shut it down, so why not tell anyone working at it ?

[@Anode_Diagnostics]

The coil may have the ionising test circuit built into it ?

[@simonparkinson1053]

No, that's in the PCM.

[@dcomputers]

It makes sense the coil is bad not firing so the computer stops the injector. It's usually if it was a bad injector the coil keeps running.

[@Dr._Diag]

Use a pocket screwdriver with a magnet, or an induction light to see if secondary side of coil is firing, if not, swap coil, and plug if you want to other cylinders, and see if misfire jumps with coil, or plug, and then go from there more in depth. 3 minutes.

[@Dr._Diag]

I like how in depth you go with scopes, and PID data for teaching purposes.

[@ScannerDanner]

that test has variables. I've seen a low compression cylinder cause a timing light (induction light) to show drop outs or misfiring, leading others to condemn and replace the ignition coil needlessly The problem was low kv demand from the low compression cylinder caused mis-triggering of the timing light

[@Dr._Diag]

@@ScannerDanner Not a timing light…. An induction light that flashes with the secondary pulse that the tech can touch to the individual ignition coils that induces enough voltage to trigger an led light to flash (indicating the coil is firing)…… Similar principle to a timing light, but no B+ power source needed. Also, the verification of the diagnoses would be SWAPPING THE SUSPECT COIL TO A KNOWN GOOD CYLINDER, and then perform a misfire monitor to ensure that the active misfire follows the suspect coil to the known good cylinder to verify faulty coil. (While you’re swapping the coil to a known good cylinder, the tech could also swap the plug from the suspect cylinder to a know good cylinder to see if it’s JUST a bad coil, or a bad plug. OR….. if BOTH known good cylinder’s plug, AND coil now misfire with suspect cylinder’s coil, AND plug, suspect a bad coil, AND fouled plug (that is, if the PCM doesn’t kill the injector on suspect cylinder, and not fouling the plug, to save the converter from over fueling, and burning converter element))…..

[@Dr._Diag]

Great video, and this path will definitely work also, just my personal preference, and seems to save me time.

[@michaelszczys8316]

" one more check, just because this is fun "

[@armenakavagian4867]

great job! I have the same jeep patriot and exactly the same error! They haven't been able to find the cause for six months now. and this all happens when the engine is cold, especially in damp weather; after warming up, it works stably. If I change the oxygen sensor, will the problem be solved?

[@ScannerDanner]

If you have the exact same error why are you asking me about the O2? We didn't do anything with the O2 on this one did we? I'm sorry, I don't remember

[@armenakavagian4867]

what solution did you find in this case? how did you solve the problem?

[@ScannerDanner]

@@armenakavagian4867 the O2 had ZERO to do with the misfire

[@armenakavagian4867]

Is there a problem with the ECU firmware?

[@ScannerDanner]

@@armenakavagian4867 nope

[@christopherhummel1904]

What scan tool is that that u use

[@ScannerDanner]

Snap-On Verus Edge

[@christopherhummel1904]

@@ScannerDanner thanks I love your videos I learn a lot from watching them looking to sign up for your scanner Danner premium soon. I wish u taught in Michigan.

[@ScannerDanner]

@@christopherhummel1904 look forward to having you! Thank you!

[@2muchy2]

Aww nothing sounds better then firing the parts cannon.